Support is requested for a collaborative research project to determine to what extent intervention can decrease the prevalence of diabetes, hyperinsulinemia, and cardiovascular risk factors among Yupik Eskimos living on St. Lawrence Island and the west coast of Alaska. The project would also investigate dietary patterns, physical activity levels, and anthropometric data and attempt to correlate these with the occurrence of diabetes, cardiovascular risk factors, diabetes complications, and insulin levels. As part of the ongoing Alaska-Siberia Medical Research Program, identical baseline data are currently being gathered in the population of Yupik Eskimos across the Bering Straits on the Chukotka Peninsula in Siberia. Age-adjusted prevalence of non-insulin dependent diabetes mellitus (NIDDM) among Alaska's Eskimos, Indians, and Aleuts overall increased 11%, from 15.7 to 17.4 per 1000 over the two-year period form 1985 to 1987 (Schraer et al., 1988 and in press). Rates in 1987 varied from 6.7 to 40.8 per 1000 in various Indian Health Service units in Alaska. These estimates are based only on clinically recognized cases. Comparing preliminary rates to Chukotka Natives 15 years and older, we find that the SL Lawrence Island rate is 9.7/1000 while the Chukotka rate is 1/1000. Since Siberian Yupik Eskimos of Chukotka and Alaska are genetically closely related, our working hypothesis is that dietary and lifestyle differences account for the difference in diabetes prevalence. We believe this represents a unique opportunity for research since these populations were essentially one until 1948, when contact ceased due to political reasons, and lifestyles diverged as a result. Initially, a survey of 800 subjects of both sexes on St. Lawrence Island and western Alaska will be carried out using similar methodology as in the ongoing Strong Heart Study among other non-Alaskan groups of Native Americans. The surveys will be followed by an intervention in which half of the participating villages will receive specific education about diet and risk factors and will be encouraged to: a) eat more traditional foods, b) decrease foods with low nutrient density such as sugar in their diet, c) decrease intake of saturated fats, and d) increase physical exercise. Additional interventions will be implemented, based on recommendations and input from the community. The "control" villages will not receive these interventions. During the fifth year of this grant the effectiveness of the interventions will be tested by a careful comparison of diabetes and cardiovascular risk factors, repeating the same survey as given during year 1. Considering that the Alaskan Eskimos began abandoning traditional diets and lifestyles only recently, it is possible that the study might lead to a reversal in this trend by providing significant insights into the etiology of NIDDM and lead to identification of the causative lifestyle factors that can be modified to prevent diabetes.